Which cranial nerve innervates the lateral rectus muscle, responsible for lateral gaze?

• A. Optic
• B. Oculomotor
• C. Trochlear
• D. Abducens

Answer: (D)

The muscle responsible for moving the eye outward (lateral gaze) is the lateral rectus, and it is innervated by the abducens nerve (cranial nerve VI). When this nerve activates, the lateral rectus contracts and pulls the eye laterally. The other cranial nerves have different roles: the optic nerve carries vision from the retina, the oculomotor nerve innervates most of the other extraocular muscles and controls eyelid elevation and pupil/ accommodation, and the trochlear nerve supplies the superior oblique. So for lateral gaze, the abducens nerve is the correct innervation.